'log in to' or 'log into'?

[Claire Conant]

Yes, there are all sorts of style guides. I have Sun, Microsoft, Chicago, NY 
Times, AP, and more in my library.  I happen to write and edit consistently 
for Microsoft platforms so I follow that guide - which I stated in my first 
post. I didn't say it was better than any other one, and possibly my second 
post would argue that attitude. My preference for finding an authoritative 
source is not by using Google or Wikipedia, although they are adequate 
reference points. I don't base my editorial decisions on them. And yes, as a 
long-time editor, one picks the style that is followed by the company and 
uses it consistently.